"Why, she scarcely needs an aerodrome at all!" Carl ventured at length. "Scarcely," replied the chief. "At any rate, not for a long time." "She is weather proof; she is wonderfully camouflaged. She could hide in a desert, or a meadow," said Max. "And she carries her own stores for a long, long trip," ventured Carl, who was just dying for the morrow to come. "And if she were chased, she could make rings round anything, even a Fokker scout, or a verdammt British S.E.5," added Max. "So you are satisfied, both of you?" asked the Rittmeister. "Perfectly satisfied. I am only longing for to-morrow, so that I may turn aerial brigand, buccaneer, or what you like," answered Carl. "And you, Max?" "I am ready, chief, to follow you to the end of the world, for mine eyes have seen the wonder ’plane." *CHAPTER III* *"TEMPEST" OF THE AERIAL POLICE* Colonel John Tempest, D.S.O., M.C., etc., late of the Royal Air Force, and now Chief Commissioner of the British Aerial Police, sat before a pile of papers in his office at Scotland Yard late one evening. He was anxious and worried, for something had gone seriously wrong with his plans. It was his duty to investigate and track down all aerial criminals, whether brigands, smugglers or revolutionists of the Bolshevist type. For this purpose he had been appointed by the Government to the command of the British Aerial Police, whose functions included the patrolling of the routes of the great aerial liners throughout the British Isles, and the All-Red route to Egypt, India, and other British possessions, and the careful guarding and watching of the aerial gateways and ports. Some of the best scout pilots of the war, including two famous secret service men, named Keane and Sharpe, were detailed to assist him in this important and ever-increasing task, for aerial crime of twenty different kinds was becoming more and more prevalent since the war. So far his efforts had been conspicuously successful, and he had brought many of the offenders to justice, but at the present moment he had to confess himself baffled--utterly baffled by a series of unfortunate occurrences which it had been beyond his power to prevent. "There is some master-mind behind all this," he exclaimed to himself, rising suddenly from his chair, and beginning to pace the room, much in the same way that he used to pace his squadron office, in the old days, when, as commander of a squadron of scouts during the Great War, he had attempted to outwit the daring of the German airmen. "I wonder now--I wonder what happened to that missing German professor!" and Colonel Tempest suddenly halted, and placed his left hand to his forehead, as some powerful, new idea had arrested his mental faculties. Then, walking across the room swiftly, he switched on a shaded light which illuminated a large map of Germany, showing the aerial routes, the lines of occupation by the Allies, etc.